The field of the invention is that of features supported by an e-mail system. More precisely, the invention relates inter alia to a method of manipulating already sent e-mails.
In the description below, like in conventional e-mail systems, an e-mail comprises a header and a body. The header contains administrative information for example the e-mail address of the sender, of the addressee(s), the time at which it has been sent. The body contains the text and the formatting of the message itself.
A common method of transmitting an e-mail over a data network is to route the e-mail's header together with the e-mail's body through several nodes of the data network according to the e-mail address of the addressee(s). Different e-mail protocols may be used in different data network. Since the sender and the addressee are not always part of the same network, some e-mail protocol conversion may be operated at gateways during the transmission of the e-mail.
Japanese Patent JP7131480 discloses a mail transmitting and receiving equipment supporting different mail modes: “new mail”, “cancel mail”, “correction mail”. A mail is sent to an addressee accompanied by the mail mode and an identifier. When the mail is received, it is handled according to the mode attached to it. By “new mail”, the mail is held together with its identifier in mail holding means. By “cancel mail”, the mail having the referenced identifier is deleted from the mail holding means. By “correction mail”, the mail having the referenced identifier is replaced by the corrected mail in the mail holding means.
A disadvantage of that solution is that the cancellation or the correction of an e-mail is visible for the addressee. He may for example have already read a mail when a “cancel mail” directed to this mail is received. However, the sender often whishes that the addressee is not informed of the modification.
Japanese Patent JP710107840 discloses an electronic mail system able to manipulate an already sent e-mail. The sender only sends a mail header to the receiver side, the mail body remains stored at the transmitter side. When a change detection section at the transmitter side detects any change of a mail, a mail change information is sent to the receiver side. The mail header corresponding to the mail which has been modified is updated thanks to an change processing section at the receiver side. Depending on a read/unread information, the user at the receiver side is informed of the change state of mails thanks to an appropriate list.
A disadvantage of that solution is that the electronic mail system is highly decentralized. The receiver has to access directly to the sender when he wants to read the body of a mail. The sender has also to be equipped of change detection means which have to check continuously whether a mail has been changed. Such a complexity at the sender is a drawback for private e-mail users.